Spinal epidural venous plexus: its MR enhancement patterns and their clinical significance.

OBJECTIVE: Evaluation of the clinical utility of enhancement of the spinal epidural venous plexus (SEVP) on postcontrast MR imaging.

MATERIALS AND METHODS: The SEVP on pre- and postcontrast T1-weighted sagittal and axial MR images were evaluated in 188 patients whose MR findings were abnormal (positive group), in 223 patients with normal MR (negative group), and in 35 volunteers. The enhancement patterns of the SEVP were graded 1 to 4 according to their degree of dilation. These three groups were compared and analyzed.

RESULTS: Epidural and intradural lesions in the positive group showed higher grades of epidural vein enhancement compared with the negative group (p = 0.01). Epidural abscesses and epidural metastases frequently showed moderate to marked dilatation of the SEVP. Degenerative disk disease with stenosis of the spinal canal exhibited more localized patterns of dilation. Most intradural lesions with cord swelling demonstrated dilation of the SEVP. Visualization of the SEVP did not differ statistically between bone and soft tissue lesions in the positive group and the negative group (p = 0.13). Evaluation of follow-up examinations showed that changes in SEVP grades were indicative of changes in disease.

CONCLUSION: SEVP enhancement patterns assist in the evaluation of disease in the spinal canal and will help to differentiate normal from pathological conditions.